1. Field of Invention
The subject invention is generally related to expandable batons and is specifically directed to a button lock configuration for locking the baton in the expanded position.
2. Description of the Prior Art
Nightsticks and batons are well known and have gained widespread acceptance as intermediate force weapons for use by law enforcement personnel. One of the best known intermediate force weapons is the ASP Expandable Baton manufactured by Armament Systems and Procedures, Appleton, Wis., the assignee of the subject invention. Typically, the ASP Baton includes three telescoping sections, the largest section defining a handle adapted for receiving and nesting the remaining sections when the baton is in the collapsed position. In the collapsed position, the baton is approximately 8 to 10 inches long and can be carried by law enforcement personnel in a suitable sheath on the belt of the uniform. The baton is adapted to be drawn quickly from the sheath and opened in a swinging action for whipping the nested sections out to an extended position and locking in position for use as an intermediate force weapon.
Examples of other extendable batons are shown in U.S. Pat. Nos. 27,335 issued to J. L. Rowe on Feb. 28, 1860; 3,371,930 issued to Y. Shiga on Mar. 5, 1968 and 4,037,839 issued to N. C. Nelson on Jul. 26, 1977.
The subject invention is specifically directed to an improvement in the type of detent mechanism for expandable batons shown in my U.S. Pat. No. 5,149,092 entitled "Locking Means for Extendable Baton" issued on Sep. 22, 1992. This patent discloses a locking means for an expandable baton including a detent button and multiple, parallel tapered stop surfaces for limiting the axial movement of the telescoping shafts of the baton. The detent button is round or spherical shaped and is positioned on each telescoping shaft of the baton. The button is biased to project outward and provides an abutment surface when the baton is in the extended position for maintaining the extended position. When the baton is in the retracted position, the button projects outward into a channel adapted to receive the button and holds the telescoping shafts in the retracted position.
While the detent button provides a simple yet effective means for locking an expandable baton in either the retracted or extended position, there is a problem with the prior art detent button as used with expandable batons. It has been found that the rapid extension of the expandable batons causes "recoil" and "bounce back" when the telescoping shafts reach the positive stop surface and the metal tube of the outer shaft contacts the metal stop surface of the telescoping shaft. This "recoil" is similar to the reaction caused when a car hits a wall, stops abruptly and then rebounds or recoils away from the wall. The same phenomenon takes place as the telescoping shaft of the baton flies forward and is stopped abruptly by the positive stop in the forward direction. The shaft then "recoils" and "bounces back" and the detent button positioned adjacent to the shaft is thrown against the surface of the mating tube.
While round or spherical buttons provide a smooth release and retraction of the telescoping shafts of the baton for easily expanded and retracting the baton, this type of button has been found to cause deformation of the button and/or the edges of the mating tube due to recoil because the line of contact between the button and the tube is along a vertical axis of the button and concentrated at a specific point. Each time the baton is whipped into the expanded position for use, the button is recoiled into contact with the mating tube which causes an indentation along the edge of the tube and may eventually deform the button. After repeated use, the telescoping shafts jam and are non-functioning.
One method of addressing the problems caused by the rapid extension of expandable batons is shown in U.S. Pat. No. 5,320,348 issued to P. D. Starrett on Jun. 14, 1994. U.S. Pat. No. 5,320,348 discloses a baton with a hollow sleeve, telescoping shaft housed within the sleeve and a stop extending from the interior wall of the sleeve for limiting forward movement of the shaft. In order to buffer the contact between the stop and shaft when the shaft is rapidly extended, the baton includes a shock absorbing means comprising a hard plastic ring and a pair of elastomeric O-rings positioned on the shaft. While buffer systems such as sleeves for the edges of the mating tubes or o-rings, as shown in U.S. Pat. No. 5,320,348, have been tried, these methods have not proven effective since the buffer is weakened after repeated use and fails to provide the necessary protection. Furthers heat treated buttons are too hard and brittle, while soft buttons are too easily deformed to be effective.
In addition to deforming the shape of the button and/or the enclosing tube, the "recoil" and "bounce back" phenomenon may cause the detent button of the prior art to tilt on the biasing spring so that the button does not sit straight on the spring, making it difficult to retract the telescoping sections. While this problem may be overcome with a stiffer spring, higher compression in the spring makes it more difficult to depress the button and retract the baton.
Therefore, there is a need for an improved detent mechanism which provides a means for selectively locking an expandable baton in either the retracted or extended position while preventing deformation of the detent lock and the telescoping sections of the baton.